Performance Pontiac Buick GMC Inc

The only thing needing replacement was the burned out headlight bulb.
I had previously noticed the headlight was not working.  Thinking it was a sealed unit I ordered a new unit and prepaid for it since it was not in stock at the dealorship.  When it arrived I made an appointment to come to the service department to have the old unit taken out and the new one put in.
My issue is that even with the new headlight unit available the survice department didn't check to see if just the bulb was defective.  Had they done that - there would have been no need to install the new unit.  It could have been returned for credit as unnecessary and I would only have been charged for the bulb and the time it took to replace it.
I didn't know enough to ask if the unit was a sealed unit.  I didn't know to ask if perhaps only the bulb was defective.
I count on the professionalism of the service department to check those simple things and report them to me.
Instead they installed an expensive but unnecessary replacement unit.   My take is that they were concerned more with profit than customer care.